Semiconductor devices are generally manufactured by various fabrication (FAB) processes that form an electric circuit on a semiconductor substrate, such as a silicon wafer. An electrical die sorting (EDS) process can be used to inspect the electrical characteristics of the electric circuit, and a packaging process can be used to separate the semiconductor substrate into individual semiconductor chips and to seal each of the semiconductor chips using an epoxy resin. Examples of FAB processes that may be used include deposition processes for forming a thin layer on the semiconductor substrate, chemical mechanical polishing (CMP) processes that polish the thin layer, photolithography processes that form a photoresist pattern on the thin layer, etching processes that etch the thin layer into an electrical pattern using the photoresist pattern as a mask, ion implantation processes that implant ions into a predetermined region of the semiconductor substrate, cleaning processes for cleaning impurities from the semiconductor substrate, and inspection processes for inspecting a surface of the semiconductor substrate so as to detect defects in the thin layer or pattern.
The above FAB processes may be performed in a clean room to which clean air is supplied. A clean room generally includes a plurality of fan filter units, a fluid supply system and a utility zone. For example, a fan filter unit can be disposed on a top portion of the clean room and can supply the clean air into the clean room from a ceiling chamber thereof. The fluid supply system can be disposed on a bottom portion of the clean room to supply various processing fluids into the clean room. A pressure controller can be disposed in the utility zone. The pressure controller controls an inner pressure of the clean room and/or the inner pressures of various unit devices that perform the above FAB processes. The clean air can be supplied into the clean room through the fan filter unit, and the clean air can be discharged into the utility zone through a bottom panel of the clean room. Accordingly, the clean air circulates through an air circulation duct connecting the ceiling chamber and the utility zone.
Examples of processing fluids include various processing gases and chemicals used for manufacturing semiconductor devices known to those of skill in the art. The fluid supply system of a clean room can include a plurality of pipes through which the various processing fluids flow and a plurality of joints for connecting the pipes to each other. The joints can include one or more valves that control the pressure and amount of the processing fluid flowing therethrough.
Processing fluid may be leaked from the joint of the fluid supply system, and the leaked fluid can circulate in the clean room through the air circulation duct that connects the ceiling chamber and the utility zone. The circulating leaked fluid can contaminate the operating environment in the clean room.